/*
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 */

/**
 *
 * @author antonio
 */


public class LevenshteinDistance {
	private static int minimum(int a, int b, int c) {
        return Math.min(Math.min(a, b), c);
	}

        public static int computeLevenshteinDistance(CharSequence str1,
                CharSequence str2) 
	{
        int[][] distance = new int[str1.length() + 1][str2.length() + 1];

        for (int i = 0; i <= str1.length(); i++)
                distance[i][0] = i;
        for (int j = 0; j <= str2.length(); j++)
                distance[0][j] = j;

        for (int i = 1; i <= str1.length(); i++)
                for (int j = 1; j <= str2.length(); j++)
                        distance[i][j] = minimum(
                                        distance[i - 1][j] + 1,
                                        distance[i][j - 1] + 1,
                                        distance[i - 1][j - 1]
                                                        + ((str1.charAt(i - 1) == str2.charAt(j - 1)) ? 0
                                                                        : 1));

        return distance[str1.length()][str2.length()];
	}
}
